Coverage improvement in wireless systems with fixed infrastructure based relays

Abstract

Infrastructure relays are used to relay signals to multi-antenna receivers where the received signals are then processed using MIMO processing. The transmissions can use spatial multiplexing and/or space time block coding.

We claim: 
     
         1 . A Multiple Input Multiple Output (MIMO) processing method, comprising:
 a first wireless node transmitting to a second wireless node;   a third wireless node transmitting to the second wireless node; and   the second wireless node performing MIMO processing on signals received from the first wireless node and the third wireless node;   wherein the third wireless node retransmits content received from a fourth wireless node.   
     
     
         2 . The method of  claim 1 , wherein the first wireless node is a mobile station. 
     
     
         3 . The method of  claim 1 , wherein the second wireless node is a base station. 
     
     
         4 . The method of  claim 1 , comprising the second wireless node adaptively selecting one of a plurality of MIMO modes by:
 for at least one MIMO mode determining at least one metric; and   selecting between the plurality of MIMO modes based at least on the at least one metric.   
     
     
         5 . The method of  claim 4 , wherein the at least one metric comprises at least one of MIMO processing gains and diversity gains. 
     
     
         6 . The method of  claim 4 , wherein the MIMO modes comprise at least one of Space Time Block Coding (STBC), Spatial Multiplexing (SM) and cooperative diversity. 
     
     
         7 . A Multiple Input Multiple Output (MIMO) processing method, comprising:
 a first wireless node transmitting to a second wireless node;   a third wireless node transmitting to the second wireless node; and   the second wireless node performing MIMO processing on signals received from the first wireless node and the third wireless node;   wherein the first and third wireless nodes receive signals from fourth and fifth wireless nodes respectively.   
     
     
         8 . The method of  claim 7 , wherein:
 the first wireless node transmits content received from the fourth wireless node to the third wireless node; and   the third wireless node transmits content received from the fifth wireless node to the first wireless node.   
     
     
         9 . The method of  claim 8 , wherein:
 the first wireless node transmitting to the second wireless node comprises transmitting a signal based on both the content received from the third wireless node and the content received from the fourth wireless node; and   the third wireless node transmitting to the second wireless node comprises transmitting a signal based on both the content received from the first wireless node and the content received from the fifth wireless node.   
     
     
         10 . The method of  claim 7 , wherein the first wireless node transmitting to the second wireless node is synchronized with the third wireless node transmitting to the second wireless node. 
     
     
         11 . The method of  claim 10 , wherein the first wireless node transmitting to the second wireless node is synchronized with the third wireless node transmitting to the second wireless node by scheduling the first wireless node transmitting to the second wireless node and scheduling the third wireless node transmitting to the second wireless node. 
     
     
         12 . The method of  claim 11 , wherein the scheduling is performed by the second wireless node. 
     
     
         13 . A Multiple Input Multiple Output (MIMO) processing method, comprising:
 selecting a group of N+M antennas to cooperate in a MIMO transmission, N being at least 2 and M being at least 1;   using Space Time Block Coding (STBC), transmitting content on the N antennas;   transmitting content on the M antennas;   performing spatial multiplexing on signals received on at least N+M antennas to extract components relating to the content transmitted by the N antennas and components relating to the content transmitted by the M antennas;   performing STBC processing on the components relating to the content transmitted by the N antennas to recover the content transmitted by the M antennas.   
     
     
         14 . The method of  claim 13 , wherein selecting a group of N+M antennas to cooperate in a MIMO transmission comprises statically defining the group of N+M antennas. 
     
     
         15 . The method of  claim 13 , wherein selecting a group of N+M antennas to cooperate in a MIMO transmission comprises dynamically defining the group of N+M antennas. 
     
     
         16 . The method of  claim 13 , wherein:
 the wireless nodes comprise at least one mobile station; and   selecting a group of N+M antennas to cooperate in a MIMO transmission comprises dynamically defining the group of N+M antennas to accommodate movement of the at least one mobile station.   
     
     
         17 . The method of  claim 13 , comprising adaptively selecting between cooperative MIMO and cooperative diversity. 
     
     
         18 . The method of  claim 17 , wherein adaptively selecting between cooperative MIMO and cooperative diversity comprises adaptively selecting between cooperative MIMO using a set of nodes and cooperative diversity using the same set of nodes. 
     
     
         19 . The method of  claim 17 , wherein adaptively selecting between cooperative MIMO and cooperative diversity comprises adaptively selecting between cooperative MIMO using a set of nodes and cooperative diversity using a different set of nodes. 
     
     
         20 . The method of  claim 17 , wherein adaptively selecting between cooperative MIMO and cooperative diversity comprises:
 for at least one of cooperative MIMO and cooperative diversity determining at least one metric; and   selecting between cooperative MIMO and cooperative diversity based at least on the at least one metric.   
     
     
         21 . A Multiple Input Multiple Output (MIMO) processing method, comprising:
 using Space Time Block Coding (STBC), transmitting content for K STBC groups on K respective groups of antennas, each group of antennas comprising N antennas, K and N each being at least 2;   transmitting content on M additional antennas, M being at least 1;   performing spatial multiplexing on signals received on at least K×N+M antennas to extract components relating to the content transmitted by the K×N antennas and components relating to the content transmitted by the M antennas;   performing a respective STBC processing on the components relating to the content transmitted by each of the K groups of N antennas to recover the content transmitted using the K STBC groups.   
     
     
         22 . The method of  claim 21 , comprising adaptively adding and removing antennas from the K×N+M antennas. 
     
     
         23 . The method of  claim 22 , comprising adaptively adding and removing antennas from the K×N+M antennas due to movement of mobile nodes. 
     
     
         24 . The method of  claim 22 , comprising adaptively adding and removing antennas from the K×N+M antennas due to movement of mobile nodes into and out of a coverage area. 
     
     
         25 . The method of  claim 21 , wherein antennas are allocated to STBC groups adaptively. 
     
     
         26 . A Multiple Input Multiple Output (MIMO) processing method, comprising:
 a first wireless node transmitting to a second wireless node;   a third wireless node transmitting to the second wireless node; and   the second wireless node performing MIMO processing on signals received from the first wireless node and the third wireless node;   wherein the third wireless node retransmits content received from the first wireless node.   
     
     
         27 . The method of  claim 26 , wherein the signals received from the first wireless node and the third wireless node are cooperative diversity transmissions. 
     
     
         28 . The method of  claim 26 , wherein the first wireless node is a mobile station. 
     
     
         29 . The method of  claim 26 , wherein the second wireless node is a base station. 
     
     
         30 . The method of  claim 26 , comprising the second wireless node adaptively selecting one of a plurality of MIMO modes by:
 for at least one MIMO mode determining at least one metric; and   selecting between the plurality of MIMO modes based at least on the at least one metric.   
     
     
         31 . A Multiple Input Multiple Output (MIMO) system comprising first, second, third and fourth wireless nodes:
 the first wireless node being configured to transmit to a second wireless node;   the third wireless node being configured to transmit to the second wireless node;   the second wireless node being configured to perform MIMO processing on signals received from the first wireless node and the third wireless node; and   the third wireless node being configured to retransmit content received from the fourth wireless node.   
     
     
         32 . The system of  claim 31 , wherein the first wireless node is a mobile station. 
     
     
         33 . The system of  claim 31 , wherein the second wireless node is a base station. 
     
     
         34 . The system of  claim 31 , wherein the second wireless node is configured to adaptively select one of a plurality of MIMO modes by:
 for at least one MIMO mode determining at least one metric; and   selecting between the plurality of MIMO modes based at least on the at least one metric.   
     
     
         35 . The system of  claim 34 , wherein the at least one metric comprises at least one of MIMO processing gains and diversity gains. 
     
     
         36 . The system of  claim 34 , wherein the MIMO modes comprise at least one of Space Time Block Coding (STBC), Spatial Multiplexing (SM) and cooperative diversity. 
     
     
         37 . A Multiple Input Multiple Output (MIMO) system comprising first, second, third, fourth and fifth wireless nodes:
 the first wireless node being configured to transmit to a second wireless node;   the third wireless node being configured to transmit to the second wireless node; and   the second wireless node being configured to perform MIMO processing on signals received from the first wireless node and the third wireless node; and   the first and third wireless nodes being configured to receive signals from fourth and fifth wireless nodes respectively.   
     
     
         38 . The system of  claim 37 , wherein:
 the first wireless node is configured to transmit content received from the fourth wireless node to the third wireless node; and   the third wireless node is configured to transmit content received from the fifth wireless node to the first wireless node.   
     
     
         39 . The system of  claim 38 , wherein:
 the first wireless node is configured to transmit to the second wireless node by transmitting a signal based on both the content received from the third wireless node and the content received from the fourth wireless node; and   the third wireless node is configured to transmit to the second wireless node by transmitting a signal based on both the content received from the first wireless node and the content received from the fifth wireless node.   
     
     
         40 . The system of  claim 37 , configured to synchronize transmissions from the first wireless node to the second wireless node with transmissions from the third wireless node to the second wireless node. 
     
     
         41 . The system of  claim 40 , configured to synchronize transmissions from the first wireless node to the second wireless node with transmissions from the third wireless node to the second wireless node by scheduling transmissions from the first wireless node to the second wireless node and scheduling transmissions from the third wireless node to the second wireless node. 
     
     
         42 . The system of  claim 41 , wherein the scheduling is performed by the second wireless node. 
     
     
         43 . A Multiple Input Multiple Output (MIMO) system, comprising:
 means for selecting a group of N+M antennas to cooperate in a MIMO transmission, N being at least 2 and M being at least 1;   means for using Space Time Block Coding (STBC), transmitting content on the N antennas;   means for transmitting content on the M antennas;   means for performing spatial multiplexing on signals received on at least N+M antennas to extract components relating to the content transmitted by the N antennas and components relating to the content transmitted by the M antennas; and   means for performing STBC processing on the components relating to the content transmitted by the N antennas to recover the content transmitted by the M antennas.   
     
     
         44 . The system of  claim 43 , wherein the means for selecting a group of N+M antennas to cooperate in a MIMO transmission comprises means for statically defining the group of N+M antennas. 
     
     
         45 . The system of  claim 43 , wherein the means for selecting a group of N+M antennas to cooperate in a MIMO transmission comprises means for dynamically defining the group of N+M antennas. 
     
     
         46 . The system of  claim 43 , wherein:
 the wireless nodes comprise at least one mobile station; and   the means for selecting a group of N+M antennas to cooperate in a MIMO transmission comprises means for dynamically defining the group of N+M antennas to accommodate movement of the at least one mobile station.   
     
     
         47 . The system of  claim 43 , comprising means for adaptively selecting between cooperative MIMO and cooperative diversity. 
     
     
         48 . The system of  claim 47 , wherein the means for adaptively selecting between cooperative MIMO and cooperative diversity comprise means for adaptively selecting between cooperative MIMO using a set of nodes and cooperative diversity using the same set of nodes. 
     
     
         49 . The system of  claim 47 , wherein the means for adaptively selecting between cooperative MIMO and cooperative diversity comprise means for adaptively selecting between cooperative MIMO using a set of nodes and cooperative diversity using a different set of nodes. 
     
     
         50 . The system of  claim 47 , wherein the means for adaptively selecting between cooperative MIMO and cooperative diversity comprises:
 means for determining at least one metric for at least one of cooperative MIMO and cooperative diversity; and   means for selecting between cooperative MIMO and cooperative diversity based at least on the at least one metric.   
     
     
         51 . A Multiple Input Multiple Output (MIMO) processing system, comprising:
 means using Space Time Block Coding (STBC) for transmitting content for K STBC groups on K respective groups of antennas, each group of antennas comprising N antennas, K and N each being at least 2;   means for transmitting content on M additional antennas, M being at least 1;   means for performing spatial multiplexing on signals received on at least K×N+M antennas to extract components relating to the content transmitted by the K×N antennas and components relating to the content transmitted by the M antennas; and   means for performing a respective STBC processing on the components relating to the content transmitted by each of the K groups of N antennas to recover the content transmitted using the K STBC groups.   
     
     
         52 . The system of  claim 51 , comprising means for adaptively adding and removing antennas from the K×N+M antennas. 
     
     
         53 . The system of  claim 52 , comprising means for adaptively adding and removing antennas from the K×N+M antennas in response to movement of mobile nodes. 
     
     
         54 . The system of  claim 52 , comprising means for adaptively adding and removing antennas from the K×N+M antennas in response to to movement of mobile nodes into and out of a coverage area. 
     
     
         55 . The system of  claim 51 , wherein antennas are allocated to STBC groups adaptively. 
     
     
         56 . A Multiple Input Multiple Output (MIMO) processing system, comprising first, second and third wireless nodes:
 the first wireless node being configured to transmit to a second wireless node;   the third wireless node being configured to transmit to the second wireless node;   the second wireless node being configured to perform MIMO processing on signals received from the first wireless node and the third wireless node; and   the third wireless node being configured to retransmits content received from the first wireless node.   
     
     
         57 . The system of  claim 56 , wherein the signals received from the first wireless node and the third wireless node are cooperative diversity transmissions. 
     
     
         58 . The system of  claim 56 , wherein the first wireless node is a mobile station. 
     
     
         59 . The system of  claim 56 , wherein the second wireless node is a base station. 
     
     
         60 . The system of  claim 56 , wherein the second wireless node is configured to adaptively select one of a plurality of MIMO modes by:
 for at least one MIMO mode determining at least one metric; and   selecting between the plurality of MIMO modes based at least on the at least one metric.